The effects of age on some of the long-term effects of chronic neuroleptics drugs will be investigated using behavioral and biochemical techniques. Young, mature and old age rats will be administered neuroleptics drugs for a 6 to 8 week period. Biochemical investigations of the effects of age and chronic neuroleptic administration in rat brain will assess HVA response to dopamine agonists and binding of agonist and antogonist to presumed receptor sites in the brain. Behavioral assessment, which will be carried out before during and after termination of chronic neuroleptic administration, will focus on measures of conditioned avoidance behavior. The research proposed extends preliminary research already conducted in Year I of grant, which investigated the effects of age in chronic neuroleptics administration on locomotor activity in stereotyped behavior, uptake of biogenic amine and MAO activity. Since the human clinical syndrome of tardive dyskinesia, persistent side-effects with long-term neuroleptic treatment in man, is more prevalent in older age population, this research will investigate whether although older age animal, exhibit more severe or prolonged evidence of supersensitivity to dopamine agonists or other persisting effects after chronic neuroleptic administration.